The Creedmoor is entirely up to the task of taking deer, bear, hogs, elk and yes, moose....
The old 6.5 Swede has been doing all of that for 100 years and more. It isn't a big cartridge, but it works.... The Creedmoor is basically identical, from a ballistic standpoint. Same 6.5mm bullets.... And the Creedmoor is definitely a "low recoil" cartridge...
The effectiveness of the cartridge is going to depend largely on the specific bullet used. I think its best used with 140 grain bullets. There are two things going for a 140 6.5mm bullet in the Creedmoor:
1) Sectional Density. Its got a lot of weight behind a small frontal area. As a result, the bullets penetration VERY deeply, even though they aren't being pushed to super fast speeds. Need an example?: two men, both weighing 180 lbs. Both stand on waist deep snow. One has snowshoes, the other doesnt. The fella with snowshoes sinks in 6 inches or so. All 180 lbs are 'spread out" over the larger surface area of the snowshoe. The other guy sinks waist deep. All 180 lbs are being placed on smaller surface area of two size 10 boots. Smaller area + decent weight + good penetration.
2) Moderate speeds. This initially seems counter intuitive. Faster seems better. But faster stresses bullets harder. They open faster and wider (see snowshoe example above) and this limits penetration, especially when the bullet scrubs off the front half of itself. With modest speeds the bullet opens a bit more slowly, and less explosively. Bullets often plow deeper....
The 6.5 Creedmoor is getting it done on elk as we speak. And the 6.5 Swede has been dropping moose for 100 plus years. Choose your bullet carefully , and you do your part, and its going to work. No. Its not an across the canyon 850 yard elk rifle. And no, it likely won't stop a charing bull moose in its tracks. But stick a 140 through the heart and lungs and that moose or elk are going to drop in 75 yards or less.
Personally, I'd look at using a Nosler Partition on the bigger critters. They open a bit more reliably at lower speeds than the TTSX and some of the other tougher bullets. A Nosler Ballistic Tip or Hornady SST would be ideal deer medicine.